Radiator Problems

[okie556]

Okay so having to replace radiator on my old 98 Buick LeSabre. While I'm at it I am going to replace top and bottom hoses as well as replace thermostat. Been a while since I tackled a project like this so is there any trade secrets when I go back together concerning filling with antifreeze.......do I need to worry about getting air lock or anything. Figured after everything was secured and tight I would fill the radiator to top as well as the reservoir bottle.........let it warm up and top off reservoir as needed. Guess I will also need to check level and add little transmission fluid. Suggestions??

 

[Dawico]

It sounds like you have it about covered. The premixed Antifreeze is easier to use, but probably a bit more expensive also. Just be sure to check it after the first road trip also, even though you are going to warm it up, there may still be air in the system.

Good luck.

 

[jocat54]

You shouldn't have any problems with that year--I would run it with the radiator cap off until the thermostat opens then top it off and secure radiator cap.


good luck


John

 

[okie556]

You shouldn't have any problems with that year--I would run it with the radiator cap off until the thermostat opens then top it off and secure radiator cap.

John

Noticed what looks like bleeder screw on top of thermostat housing. Should that be opened when warming up until anti-freeze comes out to prevent air lock??

 

[Dawico]

I wouldn't do that while the engine is running. It will spray coolant out. It may be to open and let air out when you first fill it, or to let air in when you drain it.

 

[okie556]

I wouldn't do that while the engine is running. It will spray coolant out. It may be to open and let air out when you first fill it, or to let air in when you drain it.

Okay.....thanks.

 

[TexMex247]

What Dawico said is right on about the bleeder. Open when refilling and close it when it starts to dribble out. That will purge out most of the air but not all of it. When you run it after filling, you should rev the motor up to about 2k rpm and hold it with the heater running. When the heater starts to blow hot, it means that you have purged air out of the bypass/heater system. It's ok to leave the cap on while you do this to prevent a messy overflow as the air burps out. If you see the guage creep over halfway and start to climb, you should shut the car off and then slowly open the cap to the vent position. Use precaution and a rag when doing this as it may try to "spew" out at you. The best method is to maintain downward pressure while slowly turning the cap about a third of a turn and gently letting it up. You should hear the air bubbles entering the expansion tank if the hose is hooked up near the filler neck. If the hose is off, you will hear it hiss out pressure and/or spit out some coolant. Don't be alarmed if it wants to shoot out hot antifreeze. The thing to remeber is to be patient, once you have heated up the engine enough for the thermostat to open, it may not be easy to purge it. I you simply leave the cap on and let it completely cool(a few hrs sitting) it will naturally create a vaccum that will draw coolant from the expansion tank and once the t-stat opens the air in the block should be fully displaced. Lastly, don't forget to check your transmission fluid level, usually the cooler lines going into the radiator hold only a miniscule amount, but it's still worth checking(check after driving it while idling in park). Hope this info helps - texmex

 

[okie556]

Thanks TexMex great info. Suppose to get radiator back late tomorrow afternoon.........repair shop had to replace one side of it and of course clean and pressure test. Was so weird.....was losing a little fluid over a few days time and checked all hoses & clamps. Finally drove it enough to find small crack up near where top hose outlet is. Was surprised that the parts on both sides of the cooling coils were plastic! Even more surprised that they could be replaced! Will post the end results late in the weekend.

 

[M. Sage]

Noticed what looks like bleeder screw on top of thermostat housing. Should that be opened when warming up until anti-freeze comes out to prevent air lock??

Yes. Crack it after starting the car. Wait until you see coolant coming out and retighten it.

Go easy - it's easy to break off.

 

[okie556]

Yes. Crack it after starting the car. Wait until you see coolant coming out and retighten it.

Go easy - it's easy to break off.

Okay..........radiator replacement completed! No problems or issues! That should hold the old girl for another 150,000 miles or so.